All,
This patch "fixes" the timer_cyclone code by having it initialize
fast_gettimeoffset_quotient and cpu_khz in the same manner as timer_tsc.
Ideally fast_gettimeoffset_quotient would not be used outside timer_tsc
and cpu_khz would be initialized generically outside the timer
subsystem. I have patches to do this, but they touch quite a bit of
generic code, and I'd rather not make the timer_cyclone enablement
(patch to follow) depend on these larger changes.
Comments, flames and suggestions welcome.
thanks
-john
diff -Nru a/arch/i386/kernel/timers/timer_cyclone.c b/arch/i386/kernel/timers/timer_cyclone.c
--- a/arch/i386/kernel/timers/timer_cyclone.c Mon Feb 3 11:23:11 2003
+++ b/arch/i386/kernel/timers/timer_cyclone.c Mon Feb 3 11:23:11 2003
@@ -17,7 +17,7 @@
#include <asm/fixmap.h>
extern spinlock_t i8253_lock;
-
+extern unsigned long fast_gettimeoffset_quotient;
/* Number of usecs that the last interrupt was delayed */
static int delay_at_last_interrupt;
@@ -142,6 +142,28 @@
printk(KERN_ERR "Summit chipset: Counter not counting! DISABLED\n");
cyclone_timer = 0;
return -ENODEV;
+ }
+ }
+
+ /* init fast_gettimeoffset_quotent and cpu_khz.
+ * XXX - This should really be done elsewhere,
+ * and in a more generic fashion. -johnstul@us.ibm.com
+ */
+ if (cpu_has_tsc) {
+ unsigned long tsc_quotient = calibrate_tsc();
+ if (tsc_quotient) {
+ fast_gettimeoffset_quotient = tsc_quotient;
+ /* report CPU clock rate in Hz.
+ * The formula is (10^6 * 2^32) / (2^32 * 1 / (clocks/us)) =
+ * clock/second. Our precision is about 100 ppm.
+ */
+ { unsigned long eax=0, edx=1000;
+ __asm__("divl %2"
+ :"=a" (cpu_khz), "=d" (edx)
+ :"r" (tsc_quotient),
+ "0" (eax), "1" (edx));
+ printk("Detected %lu.%03lu MHz processor.\n", cpu_khz / 1000, cpu_khz % 1000);
+ }
}
}
diff -Nru a/arch/i386/kernel/timers/timer_tsc.c b/arch/i386/kernel/timers/timer_tsc.c
--- a/arch/i386/kernel/timers/timer_tsc.c Mon Feb 3 11:23:11 2003
+++ b/arch/i386/kernel/timers/timer_tsc.c Mon Feb 3 11:23:11 2003
@@ -130,7 +130,7 @@
#define CALIBRATE_LATCH (5 * LATCH)
#define CALIBRATE_TIME (5 * 1000020/HZ)
-static unsigned long __init calibrate_tsc(void)
+unsigned long __init calibrate_tsc(void)
{
/* Set the Gate high, disable speaker */
outb((inb(0x61) & ~0x02) | 0x01, 0x61);
-
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This archive was generated by hypermail 2b29 : Fri Feb 07 2003 - 22:00:12 EST